 
Summary: Section 1.4 A Counting: Permutations
1. If you flip a coin 3 times, what are all of the possible outcomes?
How many possible outcomes are there?
2. Suppose 3 students are on a road trip, and all 3 are willing to drive.
In how many ways can they be seated in the car?
3. Four students are returning from break. If all are willing to drive,
in how many ways can they be seated in the car?
4. Definition: The Sample Space of an experiment is the set of all
possible outcomes.
5. Factorial: 0! = 1, 1! = 1, 2! = 2 × 1, 3! = 3 × 2 × 1, 4! = 4 × 3 × 2 × 1.
In general, n! = n × (n  1) × (n  2) × · · · × 2 × 1.
6. Multiplication Principal of Counting:
If one event can occur in a ways, and for each of those a ways
another event can occur in b ways, then the total number of events
is the multiplication a × b.
7. A 6 member board sits around a table. How many different seating
arrangements are possible?
8. A 6 member board self selects a president and a treasurer. In how
many ways can this be done?
9. Permutations:
